i$6 BANDICOOTS CHAP.
their back, the tails of the young being wrapped round that
of the mother. It is not only the pouched species which
carry their young in something of this fashion. Azara's
Opossum, an animal as big as a cat, is said to carry its eleven
young ones (themselves as large as rats) on the back, though
their foothold does not appear to be strengthened by inter-
twining the tails. Even with this huge family on her back, the
mother can climb trees with considerable alacrity. The mammae
FIG. 84.—Thick tailed Opossum. Didelphys crassicaudata. x|.
are seven to twenty-five in number. The genus has been lately
split up into a number of genera, Mhrmosa, Dromiciops,
Ch'ironcctes is hardly different from DidelgJiys. It has
webbed hind-feet, and is aquatic in habit. The one species of
the genus is known as the Yapock, and is a Central and South
American form. It is of about the size of a large rat, and appears
to be an expert diver after the fish upon which it lives.
Fam. 3. Peramelidae.—The Bandicoots, although clearly be-
longing to the Polyprotodont Marsupials, yet agree with the
Diprotodonts in the fact that the second and third toes of trie
feet are bound up in a common integument, which is not
the case with the Diprotodont Oaenolest.es. The hind-feet are
longer than the front; of the former limb, two or three of
the ringers alone are long and functional; the others are rudi-
mentary or absent. Tail long, hairy, and non-prehensile. Denti-
tion I-JC^ Pm-§- M-j- = 48, or sometimes, owing to the absence
of a pair of upper incisors, 46. There is a caecum.
The genus Peragcde, the Babbit-Bandicoots, consists of two